In Vitro Antibacterial, Antioxidant, Anticholinesterase, and Antidiabetic Activities and Chemical Composition of Salvia balansae

Abstract

Context: Salvia balansae de Noé (S. balansae) (Lamiaceae) is known to be an important plant used in folk medicine as an herbal remedy in Algeria. Objective: The purpose of the present study was to demonstrate the phytochemical composition, antioxidant activities, enzyme inhibitory activities, and antimicrobial activities of S. balansae extracts. Materials and methods: A methanolic extract and a petroleum ether extract from the aerial parts of the plant were assessed for their chemical composition. HPLC-MS and HPLC-DAD assessed the content of phenols, GC-MS the fatty acid composition, and ICP-MS the mineral profiles of the plant. Additionally, we evaluated the bioactivities of S. balansae extracts by the DPPH, ABTS, and CUPRAC assays, including the antioxidant potential against AChE, BChE, α-amylase, and α-glucosidase for enzyme inhibition. The antibacterial and antifungal activities of the methanolic extract were determined by the disc diffusion test against several strains of bacteria and yeasts. Results: Our findings revealed that the aerial parts of S. balansae were rich in phytochemical components and contained large amounts of minerals. Quantitative analysis of phenolic compounds by HPLC-DAD revealed the presence of 12 compounds in three major classes, flavonoids, hydroxycinnamic acid, and phenolic acid derivatives, with 0.61, 0.45, and 0.29 mg/g of extract, respectively. Nine phenolic constituents were quantified by HPLC-MS analysis; catechin (72.5%) was the main compound, followed by myricetin (21.7%). The fatty acid composition of the S. balansae petroleum ether extract by GC-MS analysis was quantified. Seventeen compounds, including palmitic acid, were identified as the major fatty acids. The antioxidant activity of the S. balansae extracts was measured by three different methods: the methanol extract provided better results than the petroleum ether extract, and interesting values were noted for the DPPH, ABTS, and CUPRAC assays of 242.7 ± 7.44, 124.1 ± 9.70, and 222.9 ± 6.05 µg/mL, respectively. The enzyme inhibition activity of the plant could not be determined. The antimicrobial results of the methanolic extract obtained from the disc diffusion method, followed by measurements of MIC, MBC, and MFC against several bacteria and yeasts, indicated that S. balansae exhibited noticeable antimicrobial and antifungal activities. Conclusions: These results provided new data about the main phenolic compounds and biological activities of extracts of the aerial parts of S. balansae, which might be an alternative source for synthetic bioactive compounds.